Fork Oil Seal for Yamaha YZF-R3: Sealed Unit
This fork oil seal is built for the Yamaha YZF-R3 and supplied to a written specification, so the part that comes off the line in the next order matches the one you approved. Fitment, base material and finish are fixed before sampling starts — that is what keeps the sealed unit programme stable once it moves from first order to repeat order.
Most buyers come to us after something went wrong: reorders that did not match the approved sample, or a specification nobody had written down. Both are avoidable when the specification is written down before bulk and the approved sample is kept as the reference.

Specification
| Part | Fork Oil Seal |
|---|---|
| Fitment | Yamaha YZF-R3 |
| Version | Sealed Unit |
| Base material | Stainless Steel |
| Typical use | Track Days |
| MOQ | 200 pieces per specification |
| Sampling | 10 working days, 3 days per revision |
| Bulk lead time | 30-60 days after approval |
| Compliance | SAE J431 |
What decides whether it lasts
- Material — Stainless Steel is the base; treat any substitution as a new approval.
- Hardness and heat treatment — recorded per lot, not per batch of paperwork.
- Fitment tolerance — checked on the actual Yamaha YZF-R3 mounting, not on a catalogue drawing.
- Finish — zinc plating holds up where the machine sees salt, mud and daily washing.
- Packing — individual packing plus inner cartons sized for the workshop bench.

Processes used on this line
- CNC machining
- injection moulding
- cold forging
- ultrasonic cleaning
- heat treatment
- die casting
Fitment notes
Keep the old part until the new one is on the bench. Comparing them side by side settles questions a photograph never will.
Where it is used
The sealed unit build is the one most often ordered for track days. Riders also fit it for daily commuting, passenger transport, security patrols, weekend riding.
Ordering
- Confirm the model year and frame number before ordering.
- Approve a sample made from the actual bulk material.
- Fix the packing and marking at quotation stage.
- Book inspection before the balance payment, not after it.
Questions buyers ask
What testing is included?
Standard lots ship with dimensional and hardness reports. SAE J431 documentation is issued with the shipment when your market requires it.
Do you handle mixed containers?
Yes. Most programmes consolidate several part numbers into one container to keep freight sensible at 200 pieces per line.
Can the specification be held on file?
Yes. Once approved, the specification is recorded against your part number so a reorder reproduces the SAE J431-compliant build instead of a fresh interpretation.
What happens if a lot fails inspection?
The lot is re-inspected against the golden sample, and replacement pieces ship on the next available booking at our cost.
Ask for the current catalogue and the specification sheet for this line.







